MORPHOLOGYCAL ADAPTATIONS

Xavier Ubach ToniazzoUniversitat de Girona

BODY FORM AND LOCOMOTION

28/03/2010

The physical properties of water.

Body form in fishes.

Modes of locomotion in fishes.

Ecology and locomotion.

An example: “The strange case of salmon”.

Conclusions.

The physical properties of water

1/13

Effective propulsion in the water Body form

Lifestyle of the fish

65000 times more viscous

Body form in fishes (I)

2/13

Body form in fishes (II)

There are a relation with body form and locomotion3/13

Modes of locomotion in fishes (I) Anguilliforms

Subcarangiforms

• Typical movement of eels.• The movement is done with all the body.• Characteristic long, thin bodies.• It’s not associated with high speed.• Fishes associated with the bentos.

• Similar to the angilliforms.• The movement is done with 2/3 body parts.• Have the ability to go back to the river.• Examples: some salmonids and cyprinids.

4/13

Modes of locomotion in fishes (II) Carangiforms

Thunniforms

• Long ondulations.• The movement is done with 1/3 body parts.• Caudal fin: rigid and sharp.• There are in open sea.

• Locomotion very specialized.• Caudal fin: robust and high crescent-shaped.• Wave movement in caudal fin. Robust body.

5/13

Modes of locomotion in fishes (III) Ostraciforms

• They have a stabilizing fins.• The movement is done with caudal fin.• Optimal habitat: rocky and coral areas.• Example: Ostracion.

6/13

Ecology and locomotion

pike

Butterfly fishTuna

Specialist acelerations

Specialist cross

Specialist maneuver

7/13

A example:“The strange case of salmon”• Salmon is the common name for several species

of fish in the salmon family (Salmonidae).

• Salmon born in freshwater, migrate to ocean and then return to freshwater to reproduce. The salmon die shortly after reproduction.

• The are salmon in the Atlantic Ocean, the Pacific and in some inland lakes.

• The European species of salmon (Salmo salar) is about 15 kg.

8/13

“The strange case of salmon” (I)• The ascent of salmon in rivers is an amazing

phenomenon that is repeated every year when it reaches the age of reproduction.

• They remain a few days in the mouths of rivers, until, having initiated sexual maturity and having it become capable of living freshwater fish, the river begins to recover.

9/13

“The strange case of salmon” (II)• Males and females together then swim upstream

overcoming seemingly insurmountable obstacles, and jumping as fast.

• During this trip upriver do not eat, so laying waste to arrive exhausted, localted in the headwaters, at 100-300 km from the coast or even more.

10/13

“The strange case of salmon” (III)• After the spawning, exhausted by so much

effort, they usually die right there, but there coming to get carried away by the stream and returned to the sea they can recover quickly.

• A couple of years living in the small salmon rivers of birth. Then it feeling

almost adults undertake the path of the sea, where he honed his development before returning to the river.

11/13

Conclusions• The body form determines most locomotrius

capabilities.

• The energy is not spent in locomotion , is available for reproduction.

• The ability of transport determines the ability to escape predators and find food.

12/13

Conclusions• Salmon born in freshwater, migrate to ocean and

then return to freshwater to reproduce. The salmon die shortly after reproduction.

• Males and females together then swim upstream overcoming seemingly insurmountable obstacles, and jumping as fast.

• After the spawning, exhausted by so much effort, they usually die right there

13/13

Thanks!!!